Apparatus and image pickup apparatus

ABSTRACT

An apparatus includes a lens, a holder, and a retainer. The lens is held with the lens being pressed against the holder by the retainer in a direction parallel to an optical axis of the lens. The lens includes a first outer periphery, a second outer periphery, a first contact portion in contact with the holder, and a second contact portion in contact with the retainer. In a direction orthogonal to the optical axis, the first outer periphery, the first contact portion and the second contact portion are arranged farther away from the optical axis than the second outer periphery. The holder is configured to hold the lens such that the holder is fitted to the second outer periphery and is not in contact with the first outer periphery.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

The aspect of the embodiments relates to an apparatus and an imagepickup apparatus.

Description of the Related Art

There is a case where a hood or an optical accessory is attached to anouter periphery of a front end of a lens apparatus. A structure forattaching the hood is, for example, such that an inner periphery of thehood is fitted to the outer periphery and then a screw provided in thehood is tightened to urge the inner periphery against the outerperiphery in a direction orthogonal to an optical axis. In thisstructure, an external member of the lens apparatus can be deformed dueto the tightening of the screw. If the external member and a holdingframe for a lens unit are integrated so that the lens apparatus has asmaller diameter or a smaller number of components, the deformation ofthe external member may deform the lens unit, resulting in changedoptical performance.

Japanese Patent Application Laid-Open No. 2016-048292 discusses a lensbarrel including an intermediate member that is formed of a resinmaterial and is arranged between a holding frame and a lens. Inaddition, Japanese Patent No. 4956680 discusses a structure forsupporting an optical element, which includes a plate spring memberbetween a holding frame and a supporting member that supports theholding frame. Furthermore, Japanese Patent Application Laid-Open No.2011-033885 discusses a lens apparatus in which a front frame is fixedto an outer periphery of a holding frame, and a hood is attached to anouter periphery of the front frame.

The configuration discussed in Japanese Patent Application Laid-Open No.2016-048292 and the configuration discussed in Japanese Patent No.4956680 require the intermediate member or the plate spring member inaddition to the holding frame, and thus are disadvantageous due to acomplex structure (the number of components). The configurationdiscussed in Japanese Patent Application Laid-Open No. 2011-033885 isdisadvantageous in terms of the external diameter of the lens apparatusbecause the front frame is fixed to the outer periphery of the holdingframe.

SUMMARY OF THE DISCLOSURE

An aspect of embodiments provides an apparatus includes a lens, aholder, and a retainer. The lens is held with the lens being pressedagainst the holder by the retainer in a direction parallel to an opticalaxis of the lens. The lens includes a first outer periphery, a secondouter periphery, a first contact portion in contact with the holder, anda second contact portion in contact with the retainer. In a directionorthogonal to the optical axis, the first outer periphery, the firstcontact portion and the second contact portion are arranged farther awayfrom the optical axis than the second outer periphery. The holder isconfigured to hold the lens such that the holder is fitted to the secondouter periphery and is not in contact with the first outer periphery.

Further features of the disclosure will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view illustrating a main part of a lens apparatusaccording to a first exemplary embodiment.

FIG. 2 is an enlarged view of a portion including a holding member inthe main part of the lens apparatus according to the first exemplaryembodiment.

FIG. 3 is a sectional view illustrating a conditional expression withrespect to an external diameter of each outer periphery according to thefirst exemplary embodiment.

FIG. 4 is a sectional view illustrating a main part of a lens apparatusaccording to a second exemplary embodiment.

FIG. 5 is an enlarged view of a portion including a holding member inthe main part of the lens apparatus according to the second exemplaryembodiment.

FIG. 6 is a sectional view illustrating a conditional expression withrespect to an external diameter of each outer periphery according to thesecond exemplary embodiment.

FIG. 7 is a diagram illustrating a configuration example of an imagepickup apparatus according to a third exemplary embodiment.

DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of the disclosure will be described with referenceto the accompanying drawings. In principle (Unless otherwise specified),the same members or the like are denoted by the same reference numeralsthroughout all the drawings for illustrating the exemplary embodiments,and the redundant description thereof will be omitted.

FIG. 1 is a sectional view illustrating a main part of a lens apparatusaccording to a first exemplary embodiment. In FIG. 1, the lens apparatusincludes a lens 1. The term “lens” refers to not only a single lens, butalso a lens unit including a plurality of lenses. A holding frame 4(also referred to as a holding member or holder) holds the lens 1. Thelens 1 is fitted to the holding frame 4. A retaining member 6 (alsoreferred to as a retainer) is screwed to the holding frame 4 and retainsthe lens 1. The lens 1 is held by the holding frame 4 while beingretained (while being urged against the holding frame 4) by theretaining member 6 in a direction parallel to an optical axis 1000. Aholding frame 5 holds lenses 2 and 3. Retaining members 7 and 8 arescrewed to the holding frame 5. The lenses 2 and 3 are held by theholding frame 5 while being retained (while being urged against theholding frame 5) by the retaining members 7 and 8, respectively, in thedirection parallel to the optical axis 1000. The holding frames 4 and 5are fixed to a fixed barrel 12, for example, with screws. A hood 9 isattached to the lens apparatus by being fitted to an outer periphery ofthe holding frame 4.

FIG. 2 is an enlarged view of a portion including the holding member inthe main part of the lens apparatus. In FIG. 2, the lens 1 fitted to afitting portion of the holding frame 4 includes a first outer periphery13 and a second outer periphery 14. The lens 1 further includes a firstcontact portion 15 and a second contact portion 16. The first contactportion 15 is in contact with the holding frame 4 while being pressedagainst the holding frame 4 (the holding member) by the retaining member6. The second contact portion 16 is in contact with the retaining member6. In the direction orthogonal to the optical axis 1000 of the lens 1,the first outer periphery 13, the first contact portion 15, and thesecond contact portion 16 are arranged farther away from the opticalaxis 1000 than the second outer periphery 14. The holding frame 4 isfitted to the second outer periphery 14 of the lens 1, and holds thelens 1 so as not to be in contact with the first outer periphery 13 ofthe lens 1.

The holding frame 4 includes a pressed portion 17 (a first pressedportion) configured to be pressed in a direction toward the optical axis1000 in the direction orthogonal to the optical axis 1000, by a pressingmember in the accessory (the hood 9 in this example) to be attached tothe outside of the holding frame 4. More specifically, tightening ascrew 10 provided in the hood 9 urges the pressing member (a plate 11 inthis example) against the pressed portion 17 (the first pressed portion)including a recessed portion or a groove portion in the holding frame 4,and fixes the hood 9 to the holding frame 4. At this time, thetightening of the screw 10 applies an external force to the pressedportion 17 of the holding frame 4 in the direction orthogonal to theoptical axis 1000, and the external force deforms the holding frame 4.The deformation (distortion) of the holding frame 4 deforms (distorts)the lens 1, which can lower the optical performance of the lensapparatus. In a conventional lens apparatus, the fitting portion of theholding frame 4 holds the lens 1 at the first outer periphery 13 thathas the largest external diameter with respect to the optical axis 1000.In contrast, the lens apparatus according to the present exemplaryembodiment is provided with the second outer periphery 14 having anexternal diameter smaller than the external diameter of the first outerperiphery 13, and has the structure in which the fitting portion isfitted to the lens 1 at the second outer periphery 14.

FIG. 3 is a sectional view illustrating a conditional expression withrespect to an external diameter of each outer periphery. Assume that theexternal diameter of the first outer periphery 13 is D1, the externaldiameter of the second outer periphery 14 is D2, and an externaldiameter of an optical surface of the lens 1 on the opposite side of thefirst contact portion 15 with respect to the second outer periphery 14in the direction parallel to the optical axis 1000 is D3. In this case,the external diameters D1 to D3 satisfy a conditional expression ofD1>D2>D3>0. In other words, in one embodiment the external diameter ofthe second outer periphery 14 be smaller than the external diameter ofthe first outer periphery 13, and larger than the smaller one of anexternal diameter of a first optical surface of the lens 1 and anexternal diameter of a second optical surface of the lens 1. This isbecause, as the fitting portion of the holding frame 4 is farther awayfrom the pressed portion 17 of the holding frame 4, to which an externalforce is applied, in the direction orthogonal to the optical axis 1000,impact of the external force on the lens 1 can be more reduced. This isalso because, as the fitting portion of the holding frame 4 is fartheraway from the optical surface having the smaller external diameter inthe same direction, impact of the external diameter on the opticalsurface can be more reduced or vignetting of light incident on the lens1 can be more suppressed. A displacement amount of a first portion (18)of the holding frame 4 facing the first outer periphery 13 and adisplacement amount of a second portion of the holding frame 4 facingthe second outer periphery 14 in a case where a force is applied to thepressed portion 17 of the holding frame 4 under specific conditions havebeen obtained by simulation. The result indicates that the displacementamount of the first portion (18) is 6.3 μm, and the displacement amountof the second portion is 5.4 μm. In this manner, according to thepresent exemplary embodiment, a deformation amount of the fittingportion of the holding frame 4 can be reduced. In the present exemplaryembodiment, a part of the first contact portion 15 and a part of thesecond contact portion 16 have equal diameters with respect to theoptical axis 1000. This can reduce deformation (change in curvature) ofthe surface of the lens 1 at the second contact portion 16 when theholding frame 4 holds the lens 1 with the retaining member 6. Forexample, in a case where the first contact portion 15 is arranged at aposition closer to the optical axis 1000 than the second outer periphery14 in the direction orthogonal to the optical axis 1000, no parts of thefirst contact portion 15 and the second contact portion 16 have equaldiameters with respect to the optical axis 1000. In this case, when theholding frame 4 holds the lens 1 while the retaining member 6 urges thelens 1, an excessively large deformation (curvature change) can occur inthe second contact portion 16 of the lens 1. Therefore, the presentexemplary embodiment can provide a lens apparatus that is advantageousin that, for example, the structure is simple, the size is compact, andthe optical performance is stable.

A lens apparatus according to a second exemplary embodiment will bedescribed with reference to FIGS. 4 to 6. FIG. 4 is a sectional viewillustrating a main part of the lens apparatus according to the presentexemplary embodiment. FIG. 5 is an enlarged view of a portion includinga holding member in the main part of the lens apparatus according to thepresent exemplary embodiment. FIG. 6 is a sectional view illustrating aconditional expression with respect to an external diameter of eachouter periphery. FIG. 4 illustrates lenses 21 and 22, and a holdingframe 23 (also referred to as a holding member) that holds the lenses 21and 22. The lenses 21 and 22 are each fitted to a fitting portion of theholding frame 23. Retaining members 25 and 26 are screwed to the holdingframe 23, and retain the lenses 21 and 22, respectively. The lenses 21and 22 are held by the holding frame 23 while being retained (whilebeing urged against the holding frame 23) by the retaining members 25and 26, respectively, in the direction parallel to the optical axis1000. The holding frame 23 is fixed to a moving barrel 24, for example,with screws. The moving barrel 24 is connected to a driving structureincluding, for example, a cam or a helicoid, and is driven by thedriving structure in a direction along the optical axis 1000. The movingbarrel 24 is driven, for example, for zooming (zoom adjustment) orfocusing (focus adjustment) in the lens apparatus.

In FIG. 5, the lens 22 fitted to the fitting portion of the holdingframe 23 includes a first outer periphery 29 and a second outerperiphery 30. The lens 22 further includes a first contact portion 31and a second contact portion 32. The first contact portion 31 is incontact with the holding frame 23 while being pressed against theholding frame 23 (the holding member) by the retaining member 26. Thesecond contact portion 32 is in contact with the retaining member 26. Ina direction orthogonal to the optical axis 1000 of the lens 22, thefirst outer periphery 29, the first contact portion 31, and the secondcontact portion 32 are arranged farther away from the optical axis 1000than the second outer periphery 30. The holding frame 23 is fitted tothe second outer periphery 30 of the lens 22, and holds the lens 22 soas not to be in contact with the first outer periphery 29 of the lens22. In addition, the holding frame 23 is configured to be adjustable inposition with respect to the moving barrel 24 in the directionorthogonal to the optical axis 1000. This enables eccentricityadjustment of a lens unit (the lenses 21 and 22). For the eccentricityadjustment, an outer periphery of the holding frame 23 includes, forexample, pressed portions 28 (second pressed portions) as cylindricalprotruding portions, at four locations on a circumference about theoptical axis 1000. More specifically, the holding frame 23 includes thesecond pressed portions configured to be pressed in the direction towardthe optical axis 1000 in the direction orthogonal to the optical axis1000, by a tool to be attached to the outside of the holding frame 23 inorder to perform eccentricity adjustment of the holding frame 23.Pressing the pressed portions 28 (the second pressed portions) along adirection indicated by an arrow 27 with the adjustment tool enables theeccentricity adjustment of the holding frame 23 (the lenses 21 and 22).The eccentricity adjustment causes an external force in the directionorthogonal to the optical axis 1000 to be applied to the pressedportions 28, and the external force deforms the holding frame 23. Thedeformation (distortion) of the holding frame 23 deforms (distorts) thelens 22. The deformation of the lens 22 is disadvantageous ineccentricity adjustment of the holding frame 23 (the lenses 21 and 22).

Assume that an external diameter of the first outer periphery 29 is D4,an external diameter of the second outer periphery 30 is D5, and anexternal diameter of an optical surface of the lens 22 on the oppositeside of the first contact portion 31 with respect to the second outerperiphery 30 in the direction parallel to the optical axis 1000 is D6.In this case, the external diameters D4 to D6 satisfy a conditionalexpression of D4>D5>D6>0. In other words, the external diameter of thesecond outer periphery 30 be smaller than the external diameter of thefirst outer periphery 29, and lager than the smaller one of an externaldiameter of a first optical surface of the lens 22 and an externaldiameter of a second optical surface of the lens 22. This is because, asthe fitting portion of the holding frame 23 is farther away from thepressed portions 28 of the holding frame 23, to which an external forceis applied, in the direction orthogonal to the optical axis 1000, impactof the external force on the lens 22 can be more reduced. This is alsobecause, as the fitting portion of the holding frame 23 is farther awayfrom the optical surface having the smaller external diameter in thesame direction, impact of the external force on the optical surface canbe more reduced or vignetting of light incident on the lens 22 can bemore suppressed. According to the present exemplary embodiment, also forthe lens subject to the eccentricity adjustment, a deformation amount ofthe fitting portion of the holding frame due to the external force canbe reduced, and a deformation amount of the lens can thus be reduced.

In addition, in the present exemplary embodiment, a part of the firstcontact portion 31 and a part of the second contact portion 32 haveequal diameters with respect to the optical axis 1000. This can reducedeformation (change in curvature) of the surface of the lens 22 at thesecond contact portion 32 when the holding frame 23 holds the lens 22with the retaining member 26. For example, in a case where the firstcontact portion 31 is arranged at a position closer to the optical axis1000 than the second outer periphery 30 in the direction orthogonal tothe optical axis 1000, no parts of the first contact portion 31 and thesecond contact portion 32 have equal diameters with respect to theoptical axis 1000. In this case, when the holding frame 23 holds thelens 22 while the retaining member 26 urges the lens 22, an excessivelylarge deformation (surface deformation or curvature change) can occur inthe second contact portion 32 of the lens 22. Therefore, the presentexemplary embodiment can provide a lens apparatus that is advantageousin that, for example, the structure is simple, the size is compact, andthe optical performance is stable.

Each of the lens apparatuses according to the first and second exemplaryembodiments could have a configuration such as one of the followingconfigurations 1 to 3. The configuration 1 is that the first outerperiphery and the pressed portion partially overlap with each other inthe direction parallel to the optical axis. When the configuration 1 isemployed, the first outer periphery and the pressed portion are close toeach other, compared to when the configuration 1 is not employed. Hence,the fitting portion is not fitted to the lens at the first outerperiphery. The configuration 2 is that the second outer periphery andthe pressed portion partially overlap with each other in the directionparallel to the optical axis. When the configuration 2 is employed, thesecond outer periphery and the pressed portion are close to each other,compared to when the configuration 2 is not employed. Hence, the fittingportion is fitted to the lens at the second outer periphery while thesecond outer periphery is arranged closer to the optical axis (fartheraway from the pressed portion) than the first outer periphery. Theconfiguration 3 is that, in the direction parallel to the optical axis,one end of the fitting portion, which is fitted to the holding member,at the second outer periphery overlaps with the pressed portion, whereasthe other end of the fitting portion does not overlap with the pressedportion. When the configuration 3 is employed, the fitting portion andthe pressed portion are far from each other, compared to when theconfiguration 3 is not employed. As a result, a deformation amount ofthe fitting portion due to the external force applied to the pressedportion, i.e., a deformation amount of the lens can be reduced.

The lens apparatus according to the first exemplary embodiment couldhave a configuration such as the following configuration 4. Theconfiguration 4 is that, the fitting portion and the pressed portion donot include portions located at the same position in the directionparallel to the optical axis. In the direction parallel to the opticalaxis, the fitting portion fitted to the holding member at the secondouter periphery does not overlap with the pressed portion. When theconfiguration 4 is employed, the fitting portion and the pressed portionare far from each other, compared to when the configuration 4 is notemployed (which includes when the configuration 3 is employed). Hence,the deformation amount of the fitting portion due to the external forceapplied to the pressed portion, i.e., the deformation amount of the lenscan be reduced (compared to when the configuration 3 is employed).

A third exemplary embodiment regarding an image pickup apparatus will bedescribed. FIG. 7 is a diagram illustrating a configuration example ofan image pickup apparatus according to the present exemplary embodiment.The image pickup apparatus includes a lens apparatus 100 including themain part of any of the above-described lens apparatuses, and an imagesensor (also referred to as an image pickup element) 200 a (included inan image pickup apparatus main body (or a camera apparatus main body)200) that captures an image formed by the lens apparatus 100. In thiscase, the lens apparatus 100 may be an apparatus exchangeably mounted onthe image pickup apparatus main body 200, or may be another apparatus.The image pickup apparatus according to the present exemplary embodimentexhibits the above-described advantageous effects regarding the lensapparatus.

While the exemplary embodiments of the disclosure have been describedabove, the disclosure is not limited to these exemplary embodiments, andvarious modifications and changes can be made without departing from thegist of the disclosure. For example, the disclosure is not limited tothe lens apparatus according to the first exemplary embodiment or thelens apparatus according to the second exemplary embodiment. A lensapparatus having both of at least part of the configuration of the lensapparatus according to the first exemplary embodiment and at least partof the configuration of the lens apparatus according to the secondexemplary embodiment may be used.

The exemplary embodiments of the disclosure can provide a lens apparatusthat is advantageous in that, for example, the structure is simple, thesize is compact, and the optical performance is stable.

While the disclosure has been described with reference to exemplaryembodiments, it is to be understood that the disclosure is not limitedto the disclosed exemplary embodiments. The scope of the followingclaims is to be accorded the broadest interpretation so as to encompassall such modifications and equivalent structures and functions.

This application claims the benefit of Japanese Patent Application No.2020-149590, filed Sep. 7, 2020, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An apparatus comprising: a lens; a holder; and aretainer, wherein the lens is held with the lens being pressed againstthe holder by the retainer in a direction parallel to an optical axis ofthe lens, wherein the lens includes a first outer periphery, a secondouter periphery, a first contact portion in contact with the holder, anda second contact portion in contact with the retainer, wherein in adirection orthogonal to the optical axis, the first outer periphery, thefirst contact portion and the second contact portion are arrangedfarther away from the optical axis than the second outer periphery, andwherein the holder is configured to hold the lens such that the holderis fitted to the second outer periphery and is not in contact with thefirst outer periphery.
 2. The apparatus according to claim 1, wherein anexternal diameter of the second outer periphery is larger than a smallerone of a diameter of a first optical surface of the lens and a diameterof a second optical surface of the lens.
 3. The apparatus according toclaim 1, wherein the first contact portion and the second contactportion have respective portions whose diameters with respect to theoptical axis equal to each other.
 4. The apparatus according to claim 1,wherein the holder includes a first pressed portion configured to bepressed in a direction toward the optical axis in the directionorthogonal to the optical axis by a pressing member in an accessory tobe attached to an outside of the holder.
 5. The apparatus according toclaim 4, wherein the first pressed portion includes a recessed portion.6. The apparatus according to claim 1, wherein the holder includes asecond pressed portion configured to be pressed in a direction towardthe optical axis in the direction orthogonal to the optical axis by atool to be attached to an outside of the holder in order to performeccentricity adjustment of the holder.
 7. The apparatus according toclaim 6, wherein the second pressed portion includes a protrudingportion.
 8. The apparatus according to claim 4, wherein the first outerperiphery and the first pressed portion have respective portions whichoverlap with each other in the direction parallel to the optical axis.9. The apparatus according to claim 4, wherein the second outerperiphery and the first pressed portion have respective portions whichoverlap with each other in the direction parallel to the optical axis.10. The apparatus according to claim 4, wherein in the directionparallel to the optical axis, one end of a fitting portion fitted to theholder in the second outer periphery overlaps with the first pressedportion, and the other end of the fitting portion does not overlap withthe first pressed portion.
 11. The apparatus according to claim 4,wherein in the direction parallel to the optical axis, a fitting portionfitted to the holder in the second outer periphery does not overlap withthe first pressed portion.
 12. An apparatus comprising: a lens; aholder; and a retainer, wherein in a direction orthogonal to an opticalaxis of the lens, a fitting portion fitted to the holder in an outerperiphery of the lens is arranged closer to the optical axis than acontact portion of the lens in contact with a contact portion of theholder which holds the lens with the retainer in a direction parallel tothe optical axis.
 13. An apparatus comprising: a lens; a holder; and aretainer, wherein in a direction orthogonal to an optical axis of thelens, a fitting portion fitted to an outer periphery of the lens in theholder is arranged closer to the optical axis than a contact portion ofthe holder in contact with a contact portion of the lens held by theholder with the retainer in a direction parallel to the optical axis.14. An image pickup apparatus comprising: the apparatus of claim 1; andan image pickup element configured to pick up an image formed by theapparatus.
 15. The image pickup apparatus according to claim 14, whereinan external diameter of the second outer periphery is larger than asmaller one of a diameter of a first optical surface of the lens and adiameter of a second optical surface of the lens.
 16. The image pickupapparatus according to claim 14, wherein the first contact portion andthe second contact portion have respective portions whose diameters withrespect to the optical axis equal to each other.
 17. The image pickupapparatus according to claim 14, wherein the holder includes a firstpressed portion configured to be pressed in a direction toward theoptical axis in the direction orthogonal to the optical axis by apressing member in an accessory to be attached to an outside of theholder.
 18. The image pickup apparatus according to claim 14, whereinthe holder includes a second pressed portion configured to be pressed ina direction toward the optical axis in the direction orthogonal to theoptical axis by a tool to be attached to an outside of the holder inorder to perform eccentricity adjustment of the holder.
 19. An imagepickup apparatus comprising: the apparatus of claim 12; and an imagepickup element configured to pick up an image formed by the apparatus.20. An image pickup apparatus comprising: the apparatus of claim 13; andan image pickup element configured to pick up an image formed by theapparatus.